The Switch is great. Some of the people I know from the net and have met a few times IRL had a launch title for it called Snipperclips which is the most adorable cooperative puzzle game ever. I need to find time to play it.
Intro about PBtA and why I love it enough to have three games going on the site:
PBtA is a fun family of games. You pretty much have all the rules for playing the game on your selected Playbook and the Basic Moves sheet; every roll is 2d6+Whatever (in this game it's normally the relevant Label, but there's a few flat rolls or things mixed up when it comes to the Nova or Doomed). A 10+ is an outright success, a 7-9 is normally a success with a downside or two (these are both called Hits), while a 6 or less is a Miss.
The Moves are both descriptive and prescriptive; these aren't skill checks or saves you're making but moments of the narrative you're trying to influence and have been deemed mechanically important enough to be left to the dice. There isn't a "push the guy into the wall" check; instead it's an automatic thing you do unless it's going to trigger one of the Moves; it could be you're unleashing your powers, or directly engaging a threat as part of this. Or it could be the fictional dressing to Piercing the Mask or Provoke them through intimidating. In Rosethorn's case it could literally be the thing you're using to Be the Monster. Or it could just be something you want to do idly as part of the story with no mechanical payoff and is just a funny aside thing you want to use to roleplay with so long as that's all you want to do with it.
The reverse is true; to do any of the Moves, you need to do what it's saying. You can't just say "I'm going to just look around the place but I'm not sticking my neck out or anything" and expect it to yield a result more than "Yep, it's a building". If you wanted more, you'd need to directly try to Assess the Situation.
Unlike other games, PBtA doesn't have the GM roll any dice; The GM generally only makes a Move against you when you roll a Miss or when things are getting boring (and unlike most other games that have a little section saying to the GM "hey, do what you like!", pbta strictly asks the GMs to trust the rules, be fair, and not pull too many things out of nowhere). Likewise, players tend to take the narrative lead and the GM puts things up as and when you engage with them.
I personally feel it's a great thing for forum games. Low number of dice rolls, most of the information out there on the net, lots of narrative control for everyone involved. And now there seems to be a pbta flavour for every genre.